WATER (Hydrologic) CYCLE
• It is a “redistribution” of water. A drought somewhere = more water somewhere else
Can you name the processes?
• http://www.teachersdomain.org/resource/ess05.sci.ess.watcyc.watercycle/
Surface water vs. Groundwater
Which is generally more polluted?
~ Surface Water
Which is harder to clean up?
~ Groundwater
Groundwater pollution sticks around...
• Very cold, no bacterial breakdown
• Very slow water movement: recharge can take 100’s or 1000’s of years
• Pollutants can stick to rocks in aquifer and pollute new water
Sources of Groundwater pollution...
• landfills
• leaky underground storage tanks
• mines
• septic tanks
• hazardous waste - deep well injection
• any pollutant in runoff that percolates
Laws• Clean Water Act – surface water
– 1972 – make water swimmable and fishable by regulating point sources
– 1977 and 1987 – storm water runoff– Section 404 – requires permit for draining,
dredging, filling wetlands• Mitigation banking
• Safe Drinking Water Act (1974) – monitors levels of contaminants in groundwater
Case Study: Natural Gas Drilling• Marcellus Shale
• Fracking - Hydraulic Fracturing
• Loophole in Safe Water Drinking Act– natural gas companies don’t have to
disclose chemicals being used
http://gaslandthemovie.com/